Electrochemical reaction orders Tafel lines

If one of the concentrations Cj is varied, the Tafel lines are shifted, and the electrochemical reaction orders xai and x b can be determined from ... 

Determination of electrochemical reaction orders from Tafel lines... 

Measurement of the Tafel lines for different concentrations, the partial electrochemical reaction orders, can be detennined from Eqs. (6.34) and (6.35). This implies that the concentration at the electrode surface remains approximately equal to the bulk concentration (elimination of the diffusion overpotential). It should be pointed out that for this evaluation the logarithm of current must be plotted versus the electrode potential and not versus the overpotential. 

From these equations the corresponding equations for Tafel lines, polarization resistance, and electrochemical reaction orders are obtained as was described in Section 6.1 for electron transfer. 

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